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THE MIRACLE OF THE IMMUNE SYSTEM - Harun Yahya

THE MIRACLE OF THE
IMMUNE SYSTEM

CELLS ON
DUTY IN THE SYSTEM

If an enemy overcomes all barriers and succeeds in entering our body,
this does not mean that the defence army has been defeated. On the contrary,
the real war has just begun, and the main soldiers come into play at this
stage. The first soldiers to meet the foe are the eater cells, that is,
phagocytes, which continuously travel in our body and keep control of
what is going on.

These are "special cleaning cells", which ingest the unwanted microbes
that have penetrated the inner surfaces of the body, and alert the defence
system when necessary.

Phagocytosis in progress. The macrophage (yellow)
while digesting the bacteria (blue).

Certain cells in the defence system capture, break down, digest, and
eliminate the miniscule particles and liquid foreign matter that have
entered our body. This event is called "phagocytosis" (cell engulfing).

Phagocytosis is one of the most important elements of the immune system.
It provides an immediate and effective protection against infections.

Phagocytes, considered the "police forces of the body," can be examined
under two separate headings.

1. Mobile police forces: These roam in the blood and
shuttle forwards and backwards between the tissues when required. These
cell units, which circulate throughout the body, also serve as scavengers.

2. Immobile police forces: These are immobile macrophages,
which are situated in the gaps in various tissues. They perform phagocytosis
on the micro-organisms from where they are, without moving.

If the invader antigens (foreign micro-organisms) are few enough for
the present eater cells to deal with, they are destroyed with no extra
alarm being given. But if the invader microbes are too great in number,
the eater cells may fail to get them under control. Unable to digest all
of them, they expand in size. When distended by the antigens, the cells
burst, causing a liquid substance (pus) to overflow. This does not mean
that the war is lost. So far, the eater cells have just met the microbes,
which have still many tougher barriers to pass. The formation of pus activates
the lymphocytes, which have been delivered from the bone marrow, the lymph
nodes, and above all, the thymus. In a second wave of defence, the newly
arriving defence cells attack everything they find around, including cell
debris, available antigens, and even old white blood cells. These defence
cells are the real eater cells - the macrophages, a type of phagocyte.

The First Aid Forces: The Macrophages

When the war becomes intense, the macrophages swing into action. Macrophages
operate in a specific manner exclusive to themselves. They do not become
involved in a one-to-one combat like the antibodies. Unlike the antibodies,
they do not work with a system similar to a bomb aimed at a single target.
Just like a gun firing lead shot, or a bomb that can be aimed at many
targets together, the macrophages can destroy a great number of enemies
together, all at the same time.

Like all other defence cells, the macrophages are also derived from the
bone marrow. The macrophages, which have a very long life span, can live
for months, and even years. Despite their small size (10-15 micrometers),
they are highly crucial for human life. They possess the ability to absorb
and digest big molecules in the cell through phagocytosis (ingestion).

Their characteristic of ingestion makes them the scavengers of the defence
system. They remove all materials that need to be cleaned up, such as
micro-organisms, antigen-antibody complexes, and other substances similar
in structure to an antigen. At the end of these processes, substances
that would be qualified as antigens are digested, and thus pose no further
threat to the organism.

General Alarm

When a country is involved in war, a general mobilization is declared.
Most of the natural resources and the budget are expended on military
requirements. The economy is re-arranged to meet the needs of this extraordinary
situation and the country is involved in an all-out war effort. Similarly,
the defence system would also announce mass mobilization, recruiting all
of its elements to fight the enemy. Do you wonder how this happens?

If enemy members are more than the currently fighting macrophages can
handle, a special substance is secreted. The name of this substance is
"pyrogen" and it is a kind of alarm call.

After traveling a long way, "pyrogen" reaches the brain where it stimulates
the fever-increasing centre of the brain. Once alerted, the brain sets
off alarms in the body and the person develops a high fever.

Above, you can see macrophages while trying
to ingest foreign materials.

The patient with a high fever naturally feels the need to rest. Thus,
the energy needed by the defence army is not spent elsewhere. The pyrogen
produced by the macrophages is perfectly designed to trigger the fever-raising
mechanism of the brain. Therefore, the macrophage, and the pyrogen, and
the temperature-raising centre of the brain, and the brain have all to
be created at the same time.

As is evident, there is a perfect plan at work. Every requirement is
created flawlessly for this plan to succeed; the macrophages, the pyrogen
substance and other similar substances, the fever-raising centre of the
brain and the fever-raising mechanisms of the body

In the absence of even one of these, the system would simply not work.
Therefore, it can by no means be claimed that such a system could have
originated step by step through evolution.

Who, then, has made this plan?

Who knows that the body's fever must rise, and that only that way the
energy needed by the defence army will not be spent elsewhere?

Is it the macrophages?

Macrophages are merely tiny cells invisible to the naked eye. They do
not have the capacity to think. They are living organisms that only obey
an established superior order; they merely carry out their duties.

Is it the brain?

Definitely no. Nor does the brain possess any power to create or produce
something. Just as in all other systems, in this system, too, it is in
a position not to give orders, but to obey orders and submit to them.

Is it man?

1. The macrophage while ingesting the bacteria
step by step. The macrophage extends forward to capture the bacteria.
2. The bacteria are captured and trapped within the extensions of
the macrophage membrane. 3. The bacteria, which are trapped in the
macrophage membrane, are absorbed one by one.

Certainly not. This system protects man from certain death, although
he is not even aware that such a perfect system is at work in his own
body. Even if man were ever ordered to develop an army in his own body
to fight the enemy and cause his fever to rise, and provide this army
to work round the clock in his entire body, he would simply have no idea
what to do.

Today, mankind is not even able to understand the details of the present
order in the defence system, despite all the technology at its disposal
- much less imitate it.

It is an obvious fact that man was created with all of his features in
place. Willingly or unwillingly, he submits to his Creator and the systems
He established. Just as everything else does...

No, everything in the heavens and earth belongs
to Him. Everything is obedient to Him. (Surat al-Baqara: 116)

Information Transfer

The macrophage (A) trying to reach out to
the bacteria (C) and entrap it with an extension called pseudopodia
(B).

Another incredible function of the macrophages is supplying the lymphocytes,
i.e., the B and T cells, which are the real heroes of the defence system,
with information about the enemy. After phagocytosing the antigen, the
antigen-presenting cells go to the lymph nodes (lymphatic tissue) through
the lymphatic channels.

This is a very important detail. Only if a cell possesses consciousness
and reason can it be capable of supplying and forwarding the information
pertaining to an enemy to the relevant centres. For the macrophage cell
to know that this information will be processed by the lymphocytes, it
has to be perfectly informed about the general strategy of the defence
system. It is very clear that the macrophage, just like all the other
cells, is the obedient element of a totally integrated system.

Top Heroes: The Lymphocytes

The lymphocytes are the main cells of the defence system. The intense
war in the body can only be won with the strenuous efforts of the lymphocytes.
The life stories of these cells are full of incredibly interesting and
wonderful stages, each of which, standing alone, is enough to demonstrate
the decrepit nature of the theory of evolution.

These bold warriors are present in the bone marrow, lymph nodes, salivary
glands, spleen, tonsils and joints. The lymphocytes are primarily present
and produced in the bone marrow.

The formation of lymphocyte in the bone marrow is one of the most mysterious
events of biology. Here, stem cells rapidly pass through a number of biological
stages and take on a completely new structure by turning into lymphocytes.
(A stem cell is an unspecialised cell that gives rise to a specific specialised
cell, such as a blood cell.) When it is considered that, despite the great
developments in genetic engineering, the transformation of even the plainest
microbe species into other similar species is considered impossible, the
mystery of this event, which takes place in the bone marrow, becomes even
greater. This mystery, unsolved by science to date, is a very simple process
for our body. For this reason, many evolutionist scientists have confessed
that natural selection or mutation tales cannot account for the mystery
in such a transformation. Prof. Ali Demirsoy stated that a complex cell
like the lymphocyte, which carries almost all the responsibility of the
war, could not have evolved from a simple cell:

Lymphocytes at war (yellow), fighting with cancer cells.

Complex cells have never been generated from primitive
cells through an evolutionary process as recently suggested.7

This fact is actually very well known by the scientists of our day. Yet,
obviously, when they accept this fact, they will equally be obliged to
accept the existence of a Creator. This is something which most of them
are very reluctant to do.

The world renowned biochemist Michael J. Behe states that evolutionists
disregard some facts for the sake of denying the being of Allah:

Also, and unfortunately, too often criticisms have
been dismissed by the scientific community for fear of giving ammunition
to creationists. It is ironic that in the name of protecting science,
trenchant scientific criticism of natural selection has been brushed aside.8

Lymphocytes, the products of this mysterious transformation, which is
one of the facts ignored, play a very interesting role in the defence
system. They check on the body cells several times a day to see if there
are any sick cells. If they find any sick or old cells, they destroy them.
There are almost 100 trillion cells in our body and lymphocytes make up
only 1%.

Now, imagine a country having an exceedingly high population, around
100 trillion. The number of health care workers (lymphocytes) would then
be 1 trillion. If we think that the world's current population is some
7 billion, the number of the people living in our imaginary country would
be almost 14 million 285 thousand times the world's population. Would
it be possible for all the members of a country with such a high population
to have a check-up one by one, and moreover, several times in the same
day?

You will surely say no, but this process is carried out in your body
every day; lymphocytes roam throughout your body several times a day to
do a health check.

Is it possible to attribute the extremely organised operation of such
a great mass of living beings to coincidence?

Can coincidences account for each one of a trillion lymphocytes assuming
such an arduous and demanding task?

Certainly not!

Allah, the Lord of all Worlds, created each one of these one trillion
lymphocytes and charged them with the responsibility of protecting man.

Lymphocytes play a very important role against major infectious diseases
such as AIDS, cancer, rabies and tuberculosis, and serious ailments such
as angina and rheumatism. Of course, this does not mean that lymphocytes
do not have any role to play with other diseases. Even the common cold
is nothing but a combat fought by the lymphocytes to keep those very dangerous
common cold viruses away from the body.

In immune individuals, killer T cells
attack and destroy cells bearing a foreign antigen, such as virus-infected
or cancerous cells. These T cells have storage vacuoles that contain
a chemical called perforin because it perforates cell membranes.
During the killing process, the vacuoles in a T cell fuse with
the cell membrane and release units of the protein perforin. These
units combine to form pores in the target membrane. Thereafter,
fluid and salts enter so that the target cell eventually bursts.

The human body can defeat many of its enemies by using antibodies. This
may lead you to wonder why lymphocytes intervene in the war directly when
they already make a considerable contribution by producing antibodies.
However, some microbes are so deadly that very strong chemical toxins
are needed for their removal. Therefore, some lymphocytes use these chemical
toxins and directly participate in the war.

How then would the defence system stop these enemies?

First, chemists and a laboratory would be needed to produce the toxin.
The structure of the required material is too special to be formed by
coincidence. Allah, Who knows that the human body will face such an enemy,
or rather, Who created such an enemy for man to take warning, has also
given the lymphocytes to synthesize this toxin.

So, is this chemical material satisfactory?

No, because this substance cannot freely circulate in the blood, as this
would mean the death of our own cells as well.

How then will this toxin be used without causing any harm to our cells?

The answer to this question is hidden in the perfection of the creation
of the lymphocytes. Toxins are placed in sacs located in the cell membrane
of the lymphocytes. This helps the chemical weapon to be used easily.
The lymphocyte injects this toxin only when it contacts the enemy cell,
eventually killing it.

The lymphocytes come in two types: B cells and T cells.

The Weapon Factories Of The
Human Body: The B Cells

Some of the lymphocytes produced in the bone marrow depart when they
mature and become fully functional, and are transported to the lymphatic
tissues through the blood. These lymphocytes are called the B cells.

B cells are the weapon factories of the body and they produce the proteins,
called antibodies, which are meant to attack the enemy.

The B Cell Pathway

A B cell during division

The cells undergo a highly complex and laborious process to become B
cells. These cells must first pass a severe test in order to become the
warriors who will protect human health.

In their initial phase, the B cells rearrange the gene fragments that
will form an antibody molecule. These genes are actively transcribed as
soon as the rearrangement is complete. At this point, it is very important
to note how a tiny cell can perform complex tasks such as arranging and
transcription. What is arranged and transcribed is actually information.
And information can be arranged and organised only by a being who possesses
intelligence. Furthermore, the outcome after the arrangement is extremely
important: this information will later be used in the manufacture of antibodies.

The transformation of B cells rapidly goes on. Upon an order coming from
an unknown source, cells produce proteins called "alfa" and "beta", which
surround the cell membrane. At a further level, a range of complicated
processes are due to take place in the cell to enable it to produce some
molecules that will enable it to bind to antigens. At the end of all these
complicated operations, the cells turn into a factory that recognises
the enemy as soon as it makes contact with it, and is able produce millions
of different weapons.

Can Every B Cell That Has Been Manufactured Stay Alive?

The more we delve into the details of the defence system, the more miracles
we encounter. As stated before, B cells manufacture antibodies. Antibodies
are weapons that are manufactured purely to cause harm to enemy cells.
So, what happens if the weapons produced by the B cell confuse their targets
and start to hit friendly cells?

In that case, the other cells send a signal inside the B cell. This signal
is actually an order for the cell to "commit suicide". Eventually, some
enzymes in the nucleus of the cell are activated and they decompose the
DNA of the cell. A perfectly working auto-control mechanism protects the
body, and finally, only the B cells that produce antibodies that cause
harm to the enemy can stay alive.

Only comprised of a compact nucleus and very little cytoplasm initially,
the B cells undergo unbelievable changes when they meet an antigen. They
divide repeatedly and build up thousands of assembly points in their cytoplasm
for the manufacture of antibodies, as well as an extensive channeling
system for the packaging and exporting the antibodies. One B cell can
pump out more than 10 million antibody molecules an hour.

Here is a single cell that transforms itself into a factory competent
enough to produce 10 million weapons an hour on meeting an enemy. If we
remember that this cell can produce different weapons for each of its
millions of enemies, we can better understand the scope of the miracle
in question here.

Some B cells become "memory cells". These cells do not immediately participate
in the body's defence, but keep molecular records of past invaders in
order to accelerate a potential war in the future. Their memory is very
strong. When the body meets the same enemy again, this time it is rapidly
geared to the appropriate weaponry production. Thus, defence becomes faster
and more efficient.

Here, we cannot help asking ourselves: "How can man, who considers himself
the most advanced being, have a memory weaker than that of a tiny cell?"

Unable to explain even how the memory of a normal human being forms and
works, evolutionists never attempt to explain the existence of such a
memory as a matter of evolution.

If a lump of flesh the size of a hundredth of a millimeter had only one
single piece of information, and used this information for the benefit
of mankind in the most accurate way, even this would be a miracle in its
own right. However, what we are referring to here goes far beyond that.
The cell stores millions of pieces of information for the benefit of man
and uses this information accurately in combinations beyond man's comprehension.
Man is able to survive thanks to the wisdom these cells display.

Memory cells are cells specially created to protect man's health. Allah
equipped them with strong memorizing ability by design. Otherwise, it
would be impossible for the cell to develop a strategy on its own accord
and give itself within this strategy the responsibility for storing information.
Moreover, the cell is even unaware of such a need; much less does it feel
the need to employ such a strategy.

In addition, there is another important question that needs to be answered
about the strong memories of the memory cells. In a normal human being,
eight million cells die every second to be replaced by new ones. Therefore,
the metabolism continuously renews itself. Yet the life span of memory
cells is much longer than the life span of other cells. This characteristic
helps them to protect people from diseases thanks to the information in
their memories. These cells, however, are not everlasting. Though a long
time later, they eventually die. At this point, we are left with a very
surprising situation. Memory cells transfer the information they possess
to the next generation before they die. People are indebted to these memory
cells for not having to be afflicted all over again by the same in diseases
they caught in infancy (measles, mumps, etc.).

How then can this cell know that it has to transfer this information?

This surely cannot be attributed to the cell itself, but to the ability
granted to it by its Creator.

How Do The B Cells Recognise The Enemy?

In a complete state of preparedness for war, the B cells then learn to
discriminate the enemies from the body cells before defending the body.

They do not need to expend much effort to do this, because these cells
and the antibodies they manufacture are able to recognise the enemy directly
from their shapes without any assistance. A receptor on their surface
meets the antigen for which it was programmed, and binds to several small
parts on it. Thus, the antigen is identified as a foreigner. In this way,
B cells can easily recognise antigens, such as bacteria.

What Is The Function Of B Cells?

A B cell covered with bacteria.

B cells are like guards who are always on the look-out for microbes.
When they encounter an invader, they rapidly divide and start to produce
antibodies. These antibodies bind to microbes like B cell receptors. The
enemy cells that are marked by the antibodies as foreigners are driven
out of the body at the end of the relentless struggle of phagocytes and
T cells. By the time the B cells inactivate the enemy with the millions
of antibodies they have produced, they have also marked it for killer
cells. Here, there is another important point, which is as important as
destroying and marking foreign cells. It is about how so many antibodies
can be produced by a limited number of genes.

As outlined in detail in the section on "Antibodies",
the B cells use the genes in the human body to manufacture antibodies.
However, the number of genes in the human body is less than the number
of antibodies produced. This situation causes no problem for the cells.
Despite all these limitations, they succeed in producing nearly 2 million
antibody types an hour.9 B cells interact in various
combinations with available genes to make the above-mentioned production.
It is literally impossible for a cell to think up these combinations.
These unconscious cells are given the ability to involve themselves in
these combinations by the will of Allah. This is because "...
When He decides on something, He just says to it, 'Be!' and it is." (Surat
al-Baqara:117)

No other force in the heavens and on the earth save Allah is capable
of ordering even a single feature of the trillions of cells. It becomes
possible only by the will of Allah that a cell performs such mathematical
operations as producing the most appropriate weapon to inactivate every
enemy that has invaded the cell.

Bacteria and viruses carry chemicals
on their surfaces called antigens. Some lymphocytes produce antibodies
to bind themselves to antigens, thus enabling the white cell to
easily ingest the bacteria. Antibodies have distinct features and
they only bind to antigens for which they are produced. As illustrated
in the above picture, a triangular antigen perfectly fits to an
antibody, which has a triangular cut. (top left). Yet the same antibody
(bottom) does not fit to a round antigen.

Brave Warriors: T Cells

Some lymphocytes migrate to the thymus after they are manufactured in
the bone marrow. The lymphocytes, which multiply and mature here, are
called T cells. These cells mature to form two different types: killer
and helper T cells. After a three-week education, T cells migrate to the
spleen, lymph nodes, and intestinal tissues to wait for the time of their
mission.

The T Cell Pathway

In comparison to B cells, T cells must go through a much more complicated
course to be ready to commence their mission. Just like B cells, they,
too, are simple cells in the beginning. These simple cells go through
a series of difficult tests to become a T cell.

In the first test, it is checked whether the cell can recognise the enemy
or not. The cells recognises the enemy with the assistance of "MHC" (Major
Histocompatibility Complex) located on the surface of the enemy, which
is a molecule that subjects the antigen to a series of chemical processes
and presents it to the T cells.

The white cells made in the lymph system tissue develop into lymphocytes
(B cells and T cells) or monocytes. Lymphocytes are key players
in immune responses. Mmonocytes can transform into large phagocytic
(engulfing) cells called macrophages.

What Is The MHC (Major Histocompatibility Complex) Molecule?

MHC is a molecule specially created
to help the T cells in recognizing the enemy. They subject the antigen
to a series of chemical processes and present it to the T cells.
With the aid of MHC molecules, virus particles, cancer cell molecules,
and even particles belonging to the inner part of a bacterium can
be detected.

There is a very important reason for
the T cells to use MHC molecules. This helps them to penetrate host
cells and locate camouflaged viruses. However, even the help of
the MHC molecule is not sufficient for T cells to fulfill their
function. T cells also need a helper cell. Called the APC (antigen-presenting
cells) for the sake of brevity, these cells break antigens apart
and grab a very important part from the antigen. This part contains
the amino acid sequence that determines the antigen's identity.
The T cell is activated when it receives this identity information
from the APCs.

As we can see, there is a need for
a superb sub-system for the defence system even to start a war.
The absence of even a single component of this intelligence network,
made up of many interconnected subunits, would render the system
useless. Under these circumstances, it would be beyond reason to
talk about coincidence in the formation of such an intelligence
system. Entertaining such views would be verging on superstition.

There is wisdom at all levels of this
system which Allah has flawlessly created. An example of this would
be the performance of APC cells that bring the enemy to T cells.
These cells are aware that T cells can recognise the enemy from
its amino acid sequence. This is one of the thousands of pieces
of evidence that both cells are created by the same power, that
is, Allah.

Either a macrophage or a B cell presents
an antigen to a helper T cell. To accomplish this, the antigen has
to be digested to peptides that are combined with an MHC protein.
The complex is presented to the T cell. In return, the helper T
cell produces and secretes lymphokines that stimulate T cells and
other immune cells.

Eventually, only those cells that are able to identify the enemy can
survive. The others are not tolerated and they are immediately destroyed.

The recognition of enemy cells alone does not ensure the survival of
T cells. These cells must also have a very good knowledge of the harmless
substances and the regular tissues of the human body so to as prevent
unnecessary conflict, which will eventually harm the body

.

The T Cell's Differentiation According To The Order
It Receives

A cell destroying itself (middle). This programmed
self-destruction is for the replacement of tissues or the elimination
of damaged cells.

The war has not yet ended for the T cells. Some T cells-to-be destroy
themselves after receiving a specific signal from other cells.

There is very limited information on the signals that cause the cells
to die a programmed death, to continue to live, or to mature and transform
themselves. From a scientific point of view, this remains one of the unsolved
mysteries of the defence system. Many similar cells in our body receive
signals from somewhere, and start functioning upon this signal. How can
these cells, which send signals to one another, be aware of the need to
send a signal? Mahlon B. Hoagland brings up the same question in his book,
The Roots of Life:

How do the cells know when to stop growing? What tells
them that the organs of which they're a part are not just the right size?
What is the nature of the division stopping signal(s)? We don't know the
answer and we continue to search for it. 10

Indeed, the mystery of the signaling between cells has not been solved
yet.

A stem cell would normally be expected to divide to form two new cells
bearing the same features. However, a switch hidden in one of the cells
is turned on causing a sudden transformation in the cell. This new cell
is the T cell that will fight for the human body. This leads us to ask
the following question:

Why does a cell transform itself into a totally different cell?

Science has not answered this question yet. Science can answer the question
of how the cell transforms itself, but it can never explain why the cell
would want to become a fighter cell. Nor can it explain who programmed
the cell to become a cell that defends the body when the need arises.

Only those who acknowledge the being of Allah can fully comprehend the
answers to these questions.

Types Of T Cells

T cells come in three groups: helper T cells, killer T cells, and suppressor
T cells. Every T cell has a special MHC molecule enabling it to recognise
the enemy.

A T cell (left) can get orders to kill from a dendritic cell (bottom
left, background) or a macrophage (bottom).

Helper T Cells

These cells can be regarded as the administrators of the system. In the
initial stages of war, they decipher the properties of the foreigner cells
absorbed by the macrophages and other antigen catcher cells. After they
receive the due signal, they stimulate killer T and B cells to fight.
This stimulation causes B cells to produce weapons called antibodies.

Helper T cells secrete a molecule called lymphokine to stimulate other
cells. This molecule somehow turns on a switch in other cells and starts
off the war alarm.

The ability of the helper T cell to produce a molecule, which activates
another cell, is a very important process.

First, the production of this molecule is related to an impending war
strategy. It is obvious that the cells cannot make up this strategy themselves,
nor can the strategy come about by sheer coincidence.

Developing a strategy would not be enough either. The molecule in the
cell, which will switch on the production key in the other cell, should
be synthesised accurately. For this, it has to be perfectly aware of the
chemical structure of the opposite cell.

A mistake made in the production of this molecule alone would paralyze
the defence system entirely. This is because an army without communication
would be destroyed even before it launched its defence.

The existence of this molecule alone suffices to prove the absurdity
of the theory of evolution. This is because the prerequisite of the system
is the existence of this molecule right from the outset. If helper T cells
failed to alert other cells with the help of this molecule, the human
body would surrender to viruses.

How
do Helper-T cells start action?
The picture illustrates how a cell breaks a microbe apart and presents
it to the T cell. As the picture at the right indicates, the T cell
will be activated only if its antigen receptor fits to the presented
antigen, if the CD4 molecule adheres to the antigen complex, and
if some other molecules (right) combine with each other. These safety
mechanisms prevent a mature T cell from moounting an immune attack
against its host.

Killer T Cells

The killer T cells are the most efficient elements of the defence system.
In previous chapters, we have studied how viruses are inactivated by proteins
called antibodies. There are cases, however, when antibodies cannot reach
out to a virus which has invaded a cell. On such occasions, killer T cells
kill the sick cell which is invaded by the virus.

A closer examination of how killer T cells kill sick cells would reveal
a great wisdom and an artistry in creation.

The killer T cells first have to distinguish between normal cells and
those in which invaders hide. They deal with this problem with the help
of the innate system (MHC molecules) granted to them. When they locate
the invaded cell, they secrete a chemical substance. This secretion sinks
into the membrane of the cell forming a hole by lining up sideways in
close formation. Following this, leaking starts in the cell which is full
of pores, and the cell dies.

Killer T cells store this chemical weapon in granular form. This way,
this chemical weapon is always kept ready for use. Scientists were amazed
to discover the fact that the cell produces its own weapon by itself and
stores it for future use. Even more amazing are the details in the mind-boggling
way the cell uses this chemical weapon.

When an enemy approaches the host cell, these microgranules move to the
tip of the cell in the direction of the enemy. Afterwards, they come in
contact with the cell membrane, melt into it, and by extending towards
the outside, they release the substance contained within them.

Killer-T cells (the small ones), which have surrounded a cancerous
cell (the large one).

Natural Killer Cells: "NK"

These lymphocytes, which are produced in the bone marrow, are also available
in the spleen, lymph node, and the thymus. Their most important functions
are killing tumour cells and virus-carrier cells.

From time to time, invader cells take very sinister courses. They sometimes
hide so well in body cells that neither antibodies nor T cells recognise
the enemy. Everything seems usual from the outside. In such cases, the
defence system somehow suspects an anomaly and "NK" cells rush to that
region through the blood. Killer lymphocytes surround the cell and start
to push the cell around. At that stage, the enemy cell is killed by a
toxigenic substance injected inside it.

How these cells identify the enemy is yet another unanswered question
about the defence system. The receptors that should be present on their
surfaces to enable them to identify of the target cells have not yet been
discovered. Therefore, the mechanism they employ in identifying the enemy
has not yet been clearly understood.

Despite all the technology at its disposal, mankind has still not been
able to solve the details of the system these cells use to identify the
enemy. Perhaps future technological advances will throw light on this
system and this subject will no longer be a mystery. This, too, would
be a piece of evidence proving the perfection of the current system, and
what an intricate plan is involved in its creation.

Blood Cells

- Thrombocytes: The coagulation of blood is considered an ordinary event,
which is largely ignored by people. However, if the perfect system which
makes this possible had not existed, human beings would experience significant
risks and even bleed to death from the slightest injuries. The thrombocyte,
which is one of the blood cells produced in the bone marrow, serves this
function. It also includes a substance called serotonin that plays an
important role in allergic reactions.

- Eosinophil: These blood cells have the ability to
perform phagocytosis, i.e. destroy (phagocytose) any foreign cells entering
the body.

- Basophil: A big, rough and single-nucleus blood cell
which is found in small quantities in the blood, and abundantly in the
dermal, splenic and intestinal connective tissues.

- Neutrophils: With an antibacterial quality, these
blood cells protect the organism against foreign materials. In addition,
they help the defence system with their phagocytosis capabilities.

The duty of these cells is to present the antigen (enemy) to the T cells.
Why a cell would serve such a function - an important responsibility -
definitely needs further consideration. It knows that the T cells defend
the human body, identify the enemy and present the enemy it captures to
the T cells for them to provide intelligence about it.

Why would the cell do this? According to the theory of evolution, this
cell should be concerned only about its own well-being. However, it serves
the system, although it receives no benefit from it.

What is even more interesting is that the APC are very well aware of
the requirements of the T cells. Based on this, the APC will break down
the enemy cell and present to the T cell only the amino acid sequence.
This means that the APC is even aware that the T cell will extract the
required information from this sequence.

At this point, it would be useful to recall one thing: We mentioned actions
such as "knowing", "calculating", "thinking", "serving". Unquestionably,
those actions require a certain consciousness. It is virtually impossible
for a being with no consciousness or will to perform these actions. Yet,
here we are talking about these abilities as being inherent in these minuscule
entities: common, tiny, unconscious cells. Therefore, who gives this consciousness,
ability, and a glorious system to these cells?

The answer to this question is very evident. It is Allah Who creates
the APC and the T cell, as well as all other cells in the body, in a harmonious
way to serve in the same system.

(Left) 1. Peptide fragment of antigen, 2.
Peptide-presenting site, 3.Antigen-presenting cell (macrophage)
Examples of APCs are macrophages. They do this by taking the foreign
material into a cavity in their cytoplasm - the part of the cell
outside the nucleus - and adding digestive chemicals to them. These
chemicals break the bacteria into fragments of the proteins from
which they are made, fragments that are now harmless, but which
can also be utilised.

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